1. Field of the Invention
The present invention relates generally to a reel brake device for preventing a tape reel in a magnetic tape cassette from turning or rotating in a direction creating slack in a tape run. More specifically, the invention relates to a reel brake device which prevents turning of the tape reel while the magnetic tape cassette is not in use, even when a vibration is exerted on the magnetic tape cassette.
2. Description of the Background Art
In a magnetic tape cassette, such as a video tape cassette (VTR cassette), a pulse-code-modulated (PCM) audio tape cassette and so forth, used with a recording and/or reproducing apparatus, a magnetic tape in a cassette housing runs from a supply reel housed within the internal space of the cassette housing, to a rotary magnetic head assembly in the body of the recording and/or reproducing apparatus, and back to a take-up reel in the cassette housing. The length of tape that contacts the head assembly in the recording and/or reproducing apparatus is outside the cassette housing and exposed when the cassette is not in use.
Conventionally, the magnetic tape cassette employs resilient braking strips to brake the magnetic tape as it travels to and from the tape reels and to avoid undesirable slack in the exposed length of the magnetic tape. However, the conventional reel brake device tends to release braking engagement to allow rotation of the tape reel to create tape slack, when the rotational force is exerted on the tape reel due to vibration. Namely, since the conventional reel brake device has a pair of braking strips for the respective supply reel and the take-up reel are formed integrally with a brake body which carries the braking strips toward and away from the locking teeth of reel flanges of the tape reels. Such construction of the conventional reel brake device tends to incline toward one tape reel when the rotational force in one direction is exerted. This causes the other braking strip to release from the locking or braking engagement with the locking teeth of the corresponding tape reel. By releasing the braking engagement, the other tape reel is allowed to rotate to create tape slack.